A foundational need in high-performance computing is to move large (multi gigabyte and even terabyte) datasets between sites. Simple file transfer mechanisms such as FTP and SCP are not sufficient from either a reliability or performance perspective. GridFTP is the de facto standard protocol for transferring large data files in production GridlHPC environments. GridFTP extends the standard FTP protocol to provide a high performance, secure, reliable data transfer protocol optimized for high-bandwidth wide area networks.